1. Field of the Invention
The present invention relates generally to an apparatus for killing microorganisms which may form in a biofilm on surfaces of implanted devices and, more particularly, to such an apparatus used with a cardiac stimulation device, e.g., a cardioverter-defibrillator (ICD), pacemaker or the like.
2. Description of the Prior Art
Infections which may occur with pacemaker/ICD devices are relatively untreatable without device removal since the bacteria live in a biofilm on the device which blocks antibiotics. When the biofilm of such an implantable device becomes infected, it is almost universally impossible to treat the infection with systemic antibiotics. The standard medical procedure is to explant the device, leading to additional costs, risks and discomfort to the patient.
The reason that device infections cannot be treated by systemic antibiotics is that the biofilm protects the bacteria from systemic antibiotics and allows them to tolerate levels of antibiotics that are several orders of magnitude above that which can safely be given to a patient.
To overcome this tolerance to antibiotics, the use of electrical fields to kill bacteria in the biofilm has been investigated and discussed. Exemplary patents include U.S. Pat. Nos. 5,312,813; 5,409,467; and 5,462,644.